Phase multiplier and modulator



Aug. 30, 1932. c. w. HANSELL 1,874,979

PHASE MULTIPLIER AND MODULATOR Filed Aug. 17. 1927 2 Sheets-Sheet l l 4 no" 60 21 1 I20 60' 2 [1 INVENTOR I CLARENCE W. HANSELL BY I TTORNEY Aug. 30, 1932. c. w. HANSELL PHASE MULTIPLIER AND MODULATOR Filed Aug. 17. 1927 2 Sheets-Sheet 2 as: h

INVENTOR CLARENCE w. ANSELL BY A TORNEY CLARENCE w.

Patented Aug. 30, 1932 j UNITED. sTATE's P TE T- FFICE rmsn MULTIPLIER Ann Monutaron Application filed August 17, 1927. Serial mfziassoj This invention relates to a phase multiplier and modulator, and to a method and means for obtaining corkscrew radiation for the elimination of fading.

Various methods for eliminating fading have been suggested, including wobbling the directivity of a directively emitted wave," or varying the plane of polarization of the transmitted wave, at frequencies lower than the transmission frequency. These methods require the use of some means to so distribute ener to the various antennae employed'that they will be excited successively, rather than simultaneously, for otherwise only a stationary resultant will be obtained. For gradual energy change, constant total load, and uniform Wobble or rotation, it is desirable that the amplitude of energization of-the individual antennae vary sinusoidally, so that only the maxima of the wave trains follow in cyclic successiom'and 'to do this is an object of my invention. This I accomplish by separately modulating portions of the transmission energy with each of the single phase components of polyphase energy of a relatively lower frequency, and then supplying the modulated portions of the transmission energy to the separate antennae, which may diifer'in plane of olari zation, or which may be directive and differ in directivity, or be directive in a single direction and have different planes of polarization, or which may be directive in different directions and have different planes of polarization. I V Inasmuch as the modulating frequency, while it may be substantially lower than the transmission frequency, should itself be a relatively high frequency, it may be desirable that it beproduced from a high frequency source such as a vacuum tube oscillator, Alexanderson alternator, or other single phase source, which requires that polyphase energy be obtained from single phase energy. This may be accomplished by using suitable inductive and capacitive reactances of proper magnitude relative to resistances to give portions of the single phase energy the necessary phase displacement to result in polyphase output. Since the polyphase energy is to be used to modulate the transmission energy, thereby requiring modulating means which preferably may take the form of electron emission tubes, and because these tubes are effective resistances in their circuits, they HANSELL, or ROCKY romnniaw You, ASSIGNOR 'ro RADIO ooaronh- TIQN or AMERICA, A CORPORATION or DELAWARE 9 may be used as the phase modifying resist ances. Accordingly itis a further object of my invention to provide a phase multiplier in which" the phase modifying resistances are themselves theuseful load.

r The invention is described in the follow- I ing specification, which is accompanied by drawings in which v Figure 1 1s a wiring diagram explanatory,

of my invention;

- Figure 2 isa diagram showing vectorially the current and potential relations in Fig ure 1' p I I p g re 3 is a wiring diagram further explanatory of my invention; V v p 1 Figures 4 and 5 showthefpotential relaf tions' obtained in Figure 3;

'Figure6 is a wiring d'agram of myinven tion;

Figure tained from each phase inFigure 6; and v Figure 8 indicates. one form ofantenna system applicable tomy invention.

1 Referringto Fi ure' 1 a source of poten p across an inductance Li. Parallel branch circuits C R and L R 1 tial E is connecte are connected across the points-a and 0 of the 7 shows the form of output obh inductance L between which there'is "a p0 tential E across points I) and c of the inductance L between which there is a potential 1 1 Togobtain a three phase energy supplythereactg ances of G and L are each made equal to tors are displaced 120, since E' 'is in phase opposition to E These relations may be explained with'the aid of the vector diagramin' Figure 2, in

A resistance R is connected' which the vector Ei represents theappliedpotential E while the 'vector E is, the part applied. to the capacitive and inductive branches. 1 The potential Ea causes a current flow .1 through the capacitive branch which leads the voltage vector .by 60?. The potential E also causes an equal currentflow.

I through the inductive branch which lags the voltage vector by 60. The current'I flowing through the resistance R causes a potential drop across the resistance which is in phase with the current and is represented by the vectorE The current I flowing thru tlie resistance R causes'apotential drop across the resistance which'is in phase with the current and is tor E g I The potential E is opposite in direction to E and is reduced in magnitude to e ual the potentials E and E and which or'uniform notation may be designated as E Figure 3 is quite similar to Figure 1, except that between the pointc and the common junction of the resistances R R and R there has been connecteda source of direct potential E ,In the actual embodiment of my invention, for the phase modifying'resistances R R and R there are used the modulator tubes, and the potential E is the normal direct anode potential for the modulator tubes. In order to allow this potential to be applied to the anode of the tube represented by the resistance R a radio frequency choke coil L is connected-in parallel with the phase modifying condenser G which may, if desired, be suitably al-, tered in magnitude so that the combined reactance of the condenser and inductance is ingly the potentials at these points are of interest inorder to study the operation of properly capacitive.

The'points T T and T represent the points of connection of the anodes of the modulator tubes T T and T and accordthe modulator circuits. Referring to F igure 4 the horizontal line E represents the steady positivev anode potential which-nor: m'ally would be applied to the anodes of the tubes T ,T and T were the source E out out of circuit. The applied potential E in Figure 2, is preferably of such magnitude that the maxima of the ,dephased potentials Em, E and E indicated in Figure 2, will be equal to the steady anode potential E as is indicated in Figure 4.7 The resultant potential applied to the tube anodes will be the instantaneous sum of the alternating and direct potentials, as. is indicated by the curves E E and VE in Figure 5. It is thus seen that the anode potentials of: the modu- V lator tubes vary between zero and a maximum sinusoidally, and that these maxima are displaced 120 in phase,

, Figure 6 may now be considered, and in this figure it will be recognized that T T and T are the three modulator tubes, G is a source of single phase modulating potential, L is the inductance across which the potentials E and E are obtained in phase opposition, L is a phase modifying inductance, C is a phase modifying condenser, and L is the radio frequency choke Which perrepresented I by the vecmits the direct potential from the source E to reach the anode of the tube T If G is a vacuum tube source it is pref-' and C and the resonant output circuits L C 7 Ci, and Lg G5, which are tuned to the transmission frequency, and which ordinarily, therefore, will be markedly detuned with respect to the modulating frequency of the generator G Tothe' inductances of these output circuits the three phase lines 11, 12,

and 13 may be coupled by means of the coupling inductances L L and L a r r The grid circuits of the modulator tubes are connected in parallel withone another,

and across an input inductance L which is in series with a source of grid biasing potential E The source of transmission energy of high frequency is connected to the coil L which is magnetically to the input induct ances L j V The phase modifying efi'ectof the ouput circuitmay be disregarded because all of the current vector-s Will be shifted in the same direction, and the difference in the amount of their displacement will be a second order difference, and therefore, negligible, or, if de sired, their impedance value may, be taken into consideration when the reactances are selected. I V i Figure 7 shows a wave of transmission frequency modulated'by one phase of theipolyphase modulating energy, and it isclear that the actual output from the phase multiplier and modulator will consist of three such modulated high frequency ,waves, the maxima of which will be displaced 120 in phase,

- In Figure 8 there are shown three directive antennae, l, 2, and 3, which consist of a series of radiators connected by transmission lines 21, 22, and 23, which in turn are fed from three lines 11, 12, and 13. For a more detailed description of these antennae my copending application, Serial Number 161,771, filed Jan. 18, 1927, and a copending applicaphase modifying tion of Nils E. Lindenblad, Serial Number rectivity are slightly diflerent- It is clear that the phase multiplier, and modulator may be used toobtain an energy supply for use with antennae which are differently located but focused on asingle objective, or which are differently or similarlylocated and different: 1y directive, or displaced in plane of polarization, or for directiveantennae focused on a single objective while displaced in plane of polarization, as well as fordifi'erent polariza- 1,874,979 V I I 3 tion and difierent directivity as has been illustrated in Figure 8.

The variation of the plane of polarization i will be a uniform rotation of a wave of coni I 5 stant amplitude, for the wave may be represented by a vector which is the resultant of the instantaneous vectors representing the in- I dividual antennae, and the constant length and uniform rotation of such a resultant vector is one of the well known properties of a balanced three phase circuit. By the means here disclosed a true corkscrew wave maybe radiated, or a uniform wobble may be obtained, while the load on the energy sources is 1 l kept constant, and the energy changes in the antennae are made sinusoidally, which is a Variation of least shock and consequently greatest efiiciency. i

I claim:

A three phase modulator comprising first, second, and third modulator tubes, an input circuit coupled to the cathodes and control electrodes of the modulator tubes, a source of direct energy for the tube anodes, a source of modulating energy for changing the effective anode potentials, means coupling the modulating source to the anode of the first tube, means coupling the modulating source in reversed polarity thru a capacitor to the anode of the second tube, means coupling the modulating source in reversed polarity thru an inductor to the anode of the third tube, and

tput circuits for the modulator tubes.

CLARENCE W. HANSELL. 

